# Extract.linim

##### Extract Subset of Pixel Image on Linear Network

Extract a subset of a pixel image on a linear network.

##### Usage

```
# S3 method for linim
[(x, i, …, drop=TRUE)
```

##### Arguments

- x
A pixel image on a linear network (object of class

`"linim"`

).- i
Spatial window defining the subregion. Either a spatial window (an object of class

`"owin"`

), or a logical-valued pixel image, or any type of index that applies to a matrix, or a point pattern (an object of class`"lpp"`

or`"ppp"`

), or something that can be converted to a point pattern by`as.lpp`

(using the network on which`x`

is defined).- …
Additional arguments passed to

`[.im`

.- drop
Logical value indicating whether

`NA`

values should be omitted from the result.

##### Details

This function is a method for the subset operator `"["`

for
pixel images on linear networks (objects of class `"linim"`

).

The pixel image `x`

will be restricted to the
domain specified by `i`

.

Pixels outside the domain of `x`

are assigned the value `NA`

;
if `drop=TRUE`

(the default) such `NA`

values are deleted
from the result; if `drop=FALSE`

, then `NA`

values are retained.

If `i`

is a window (or a logical-valued pixel image)
then `x[i]`

is another pixel image of class `"linim"`

,
representing the restriction of `x`

to the spatial domain
specified by `i`

.

If `i`

is a point pattern, then `x[i]`

is the vector of
pixel values of `x`

at the locations specified by `i`

.

##### Value

Another pixel image on a linear network (object of class `"linim"`

)
or a vector of pixel values.

##### Examples

```
# NOT RUN {
M <- as.mask.psp(as.psp(simplenet))
Z <- as.im(function(x,y){x}, W=M)
Y <- linim(simplenet, Z)
X <- runiflpp(4, simplenet)
Y[X]
Y[square(c(0.3, 0.6))]
# }
```

*Documentation reproduced from package spatstat, version 1.55-1, License: GPL (>= 2)*